SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '953c2c0ac0c84e07409cb96f81341bb35958b4e7efa4c67dd43e4815377dbc16' 
  AND token = 'UDI7lKkIZIThbk+tuWGwPTjCl952WIlHIPko2ZTvlOk=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00019

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}